Device for guiding a load chain in a hoisting and pulling apparatus



April 30, 1968 MIYOSHI KITO DEVICE FOR GUIDING A LOAD CHAIN IN A HOISTING AND PULLING APPARATUS Filed Oct. 26, 1966 FIG.2 FIG. 5

KITO

m m w m w W M A TTORNE YS United States Patent 3,380,712 DEVICE FOR GUIDING A LOAD CHAIN IN A HQISTING AND PULLING APPARATUS Miyoshi Kite, 745 Seijo-machi, Setagaya-ku, Tokyo, Japan Filed Get. 26, 1966, Ser. No. 589,725 Claims priority, application Japan, Dec. 20, 1965, ill/78,069, 40/78,il70 1 Claim. (Cl. 254-467) ABSTRACT OF THE DISCLGSURE A hoisting device includes a rotatable sprocket for a link chain, the link chain extends downwardly from the sprocket on a load side and, on the free side, extends through a chain guide for guiding the links of the chain away from the sprocket and into a storing bucket. The chain guide includes a tubular element defining cross grooves which extend at substantially 90 and which are located to guide the chain downwardly in a smooth curve away from the sprocket and thence to the top of the storing bucket so that the chain can be fed into the bucket. In this arrangement the chain does not extend downwardly on the free side to interfere with the lifting of the load. The device also includes means for holding the chain onto the sprocket directly before the chain guide and means for lifting the chain off the sprocket directly at the chain guide for transportation through the guide to the storage bucket.

Summary of the invention This invention relates, in general, to the construction of chain hoists and, in particular, to a new and useful chain hoist having means for guiding the chain from a rotatable Sprocket upwardly into a chain collecting bucket which may be mounted on the frame of a hoist member at a position above or even with the chain sprocket or guide pulley.

The present invention is an improvement over the prior art construction of chain hoists particularly in respect to the provision of a guide for the chain which permits the chain of the hoist to be guided upwardly into a storage bucket which may be maintained above the lower end of the holding frame for the guide pulley. With chain hoists constructed heretofore it was necessary to store the free length of chain being collected during the lifting of a load in a chain bucket which was located either on the ground or at a location below the bottom of the chain guide pulley of the hoist. A disadvantage in such an operation is that the free chain length interferred with the lifting or it prevented the hoist apparatus from being lowered to an extent which may be necessary for the engagement and lifting of a particular piece of equipment.

A further advantage of the present invention over the prior art is that the frame for the hoist is provided with a chain guide which insures the proper feeding Of the chain away from the pulley during the lifting procedure and also the separation or detachment of the chain from the engaged sprocket at the most advantageous position.

Accordingly and in accordance with the invention, there is provided a hoist which provides the highest possible lift for a load and which includes means for guiding the ree side of a load chain into the hoist supporting frame structure at a location such that it does not interfere with the load being lifted.

A further object of the invention is to provide a chain hoist with guide means for feeding the chain surely and smoothly.

A further object of the invention is to provide a chain hoist which includes a frame structure and in which is rotatably mounted a sprocket for the load chain Which may be either manually or automatically driven and which includes on the frame structure preferably above the sprocket a storing bucket for the free side of the chain with means for guiding the chain upwardly to the top of the storing bucket for deposit downwardly therein.

A further object of the invention is to provide a lifting device which is simple in design, rugged in construction and economical to manufacture.

The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this specification. For a better understanding of the invention, its operating advantages and specific objects attained by its use, reference should be had to the accompanying drawings and descriptive matter in which there is illustrated and described a preferred embodiment of the invention.

In the drawings:

FIG. 1 is a side elevational view partly insection of a chain hoist constructed in accordance with the invention;

FIG. 2 is a section taken on the line 2-2 of FIG. 1;

FIG. 3 is a section taken on the line 33 of FIG. 1; and

FIG. 4 is a section similar to FIG. 2, but showing another embodiment of the invention.

Referring to the drawings, in particular, the invention embodied therein comprises a chain hoist generally designated 21 which includes a frame body or mounting block 1 at the lower end of which is rotatably mounted a hoisting pulley or sprocket 2. The sprocket 2 includes a shaft 2a which is advantageously driven from either an electric motor or a hand operated sprocket (not shown). The frame body 1 advantageously includes a hook 22 at the upper end thereof for suspending the body from a supporting beam or movable crane, for example.

In accordance with the invention, the hoist 20 provides means for guiding and storing the free side of a lifting chain 3 in a manner such that it will not in any way interfere with the lifting of a load which is to be secured to the hook 4. In order to accomplish this purpose, it is desirable that the means for storing the chain which comprises a storing bucket 6 mounted on the frame 1 should not project beyond the bottom of the frame 1 so as to either interfere with the lifting of a load or to limit the height to which the lifting frame 1 may be operable. For example, when the hook 22 is suspended from a further chain element which may be raised or lowered, it is desirable that the space below the lifting pulley 2 be unhindered or unblocked so that the frame 1 may be lowered as far as possible.

In accordance with a feature of the invention, the stor age bucket 6 may advantageously be mounted either within the frame 1 or on the exterior thereof in a position at which it will not interfere with any reduction gearing (not shown) when located within the frame.

A further feature of the invention is the provision of a guide means which includes a curved guide frame member 7 and a detachment piece 8 which is connected to the frame 1 immediately below the free side of the pulley 2 in order to detach the free end 5 of the chain from the pulley during the winding up or lifting of the load. In the preferred arrangement, the uide 7 includes grooves 10 formed at apart providing spacing guides for the chain link 5 to insure that the chain is fed evenly around in a curve from the pick off point adjacent the detachment piece 8 upwardly above the top of the collecting bucket 6. As the chain is pushed up, it is permitted to drop into the collecting bucket 6 and to accumulate as indicated. When the sprocket is made to rotate in a reversed direction, that is, clockwise as indicated in FIG. 1, then the chain 3 passes through the guide 7, in a reversed direction and the hook 4 is lowered.

In some instances, it is desirable to also provide the r 9 as a guide means 7 with means 9 for insuring that the chain is held onto the pulley 2 during the portion of its travel from the top of the pulley around to its detachment at the location of the detachment piece 8. As indicated in FIG. 3, the chain holder 9 is provided with grooves or an opening to facilitate alignment of the chain and feeding thereof as it is being directed around the pulley to the guide 7.

By the construction of the hoist, in accordance with the invention, it is assured that the load chain will be engaged at the sprocket wheel in a uniform manner around a desired portion of the periphery of the wheel and will be surely released from the wheel at a predetermined position. By providing the guide with the detachment piece, it is assured that the chain will be disengaged from the periphery of the chain sprocket and smoothly and surely guided through the guide grooves provided in the member around and upwardly for deposit into the chain storage bucket 6. The chain guide means 7 is such that the chain is guided in the manner of a flexible rod member upwardly against the action of gravity to a location at which it may easily drop down into the bucket.

In the embodiment of FIG. 4, the guide 7' which is made similar to the guide 7 of FIG. 1 may be made up of a plurality of separate channel members 11 arranged in rectangularly oriented relationship to form channels or guideways similar to the grooves 10 shown in FIG. 2. The guide 7' is oriented on the left of the pulley as shown in FIG. 1 or to the right of the pulley in the event the load chain is to extend downwardly on the left side of the pulley, The guide 7 is also advantageously straight to provide for directing the chain off the pulley in substantially a straight line tangent to the top of the pulley, for example. In this event, a bucket similar to the bucket 6 would be located on the right side of the pulley.

In the embodiment illustrated, the frame body is indicated as being formed at a portion of a portable chain hoist but, of course, the frame body may be fixed in position and permit functioning of the guide for the free length of the chain in the same manner.

While a specific embodiment of the invention has been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles.

What is claimed is:

1. A chain hoist comprising, in combination, a frame body; a chain sprocket rotatably mounted on said body adjacent the lower end thereof; hoist suspension means at the upper end of said body; a lifting chain engaged around the upper periphery of said sprocket and having a load side depending from one side of said sprocket, said chain comprising interlooped links adjacent ones of which, under load, lie in mutually substantially perpendicular planes; a chain storage bucket on said body above said sprocket and laterally completely within the peripheral outline of said body, said bucket having a bottom, a side wall and an open upper end to receive the free side of said chain within said bucket; a relatively elongated continuous tubular guide on said body receiving the free side of chain and guiding the free side into said bucket, said guide having an upwardly extending and opening entry section adjacent the opposite side of said sprocket menging in a smooth outwardly and upwardly extending curve into an upwardly extending intermediate section which merges in a smooth inwardly and upwardly extending curve into an exit section having an open chain exit end disposed above the open end of said bucket and laterally at a position where the exiting free side of said chain will depend substantially centrally into said bucket; the interior of said guide having a cruciform cross-section including two mutually perpendicular arms each guiding a respective one of each pair of adjacent chain links; and chain stripping means operatively associated with said sprocket and the upwardly opening entry section of said guide to strip the free side of said chain from said sprocket.

References Cited UNITED STATES PATENTS 1,458,354 6/1923 Neller 254-167 1,591,362 7/1926 Cofling 254167 1,807,466 5/1931 Birkenmaier 254-170 2,859,937 11/1958 Robins 254-167 EDWARD A. SROKA, Primary Examiner.

EVON C. BLUNK, Examiner,

H. C. HORNSBY, Assistant Examiner. 

